You're right, regener8ed. The air seems to come from up under the chin, too. I was thinking about getting that air dam thingy to try and alleviate that problem.
And the shield thing is annoying, too. One click open, it will slam shut on you at about 25mph. I was gonna try and see if there is an adjustment I can make to that....

 

I just bought a exo-400 the other day, and the sales man convinced me that I get M instead of L becuase 'the padding WILL compress significantly after a while' (quoted from the salesman). So even the L fits very nicely, (the M is kinda hard to put on, but once its on then it's not that bad), I picked up the M. So my question is does the padding really compress that much after a while?

 

I have same issue with Hikeetech when I first bought the helmet. I wear L and it was very very tight to the point give me headache. After short period of time, they fit really nice now. I still want to try XL just to see if it more comfortable but I am afraid after a while, it will be loose on my head.